10.5. Calculator
The Calculator is much more than a simple four-function memory calculator. It can also
act as a scientific calculator for students and scientists, a conversion calculator for metric
and U.S. measures, and even a currency calculator for world travelers.
The little Calculator widget in the Dashboard is quicker to open, and it's great for quick
four-function number crunches. But the standalone Calculator program is far more
powerful. For example:
• The calculator has three modes: Basic, Advanced, and Programmer (Figure 10-1).
Switch among them by choosing from the View menu (or pressing -1 for
Basic, -2 for Advanced, or -3 for Programmer).
Tip: You can also cycle among the three modes by repeatedly clicking what, on
most windows, is the Zoom button (the green round dot at upper left). It's a first
for the Mac—a Zoom button that changes function each time you click it—but it's
kind of neat.
• You can operate the calculator by clicking the onscreen buttons, but it's much
easier to press the corresponding number and symbol keys on your keyboard.
• you go, you can make Calculator speak each key you press. The Mac's voice
ensures that you don't mistype as you keep your eyes on the receipts in front of
you, typing by touch.
Just choose Speech Speak Button Pressed to turn this feature on or off. (You
choosewhich voice does the talking in the Speech panel of System Preferences.)
Tip: If you have a laptop, don't miss the embedded numeric keypad, superimposed
on the right side of the keyboard and labeled on the keys in a different color ink.
When you press the Fn key in the lower-left corner of the keyboard, typing these
keys produces the numbers instead of the letters. (You can also press the
NumLock key to stay in number mode, so you don't have to keep pressing Fn.)
• Press the C key to clear the calculator display.
• Once you've calculated a result, you can copy it (using Edit Copy, or -C)
and paste it directly into another program.
• The Calculator even offers Reverse Polish Notation (RPN), a system of entering
numbers that's popular with some mathematicians, programmers, and engineers,
because it lets them omit parentheses. Choose View RPN to turn it on and off.
Tip: How cool is this? In most programs, you don't need Calculator or even a Dashboard
widget. Just highlight an equation (like 56*32.1-517) right in your document, and press
-Shift-8. Presto—Mac OS X replaces the equation with the right answer. This trick
works in TextEdit, Mail, Entourage, FileMaker, and many other programs.And if you
ever find that it doesn't work, remember that the Spotlight menu is now a calculator, too.
Type or paste an equation into the Spotlight search box; instantly, the answer appears in
the results menu.
Figure 10-1. The Calculator program offers a four-function Basic mode, a full-
blown scientific calculator mode, and a programmer's calculator (shown here, and
capable of hex, octal, decimal, and binary notation). The first two modes offer a
"paper tape" feature (View Show Paper Tape) that lets you correct errors
made way back in a calculation.
To edit one of the numbers on the paper tape, drag through it, retype, and then click
Recalculate Totals. You can also save the tape as a text file by choosing File
Save Tape As, or print it by selecting File Print Tape.
10.5.1. Conversions
Calculator is more than a calculator; it's also a conversion program. No matter what units
you're trying to convert—meters, grams, inches, miles per hour—the Calculator is ready.
Truth is, the Units Converter widget in Dashboard is simpler and better than this older
Calculator feature. But if you've already got the Calculator open, here's the drill:
1. Clear the Calculator (for example, type the letter C on your keyboard). Type in the
starting measurement.
To convert 48 degrees Celsius to Fahrenheit, for example, type 48.
2. From the Convert menu, choose the kind of conversion you want.
In this case, choose Temperature. When you're done choosing, a dialog box
appears.
3. Use the pop-up menus to specify which units you want to convert to and from.
To convert Celsius to Fahrenheit, choose Celsius from the first pop-up menu, and
Fahrenheit from the second.
4. Click OK.
That's it. The Calculator displays the result—in degrees Fahrenheit, in this
example.
The next time you want to make this kind of calculation, you can skip steps 2, 3, and 4.
Instead, just choose your desired conversion from the Convert Recent Conversions
submenu.
Calculator is especially amazing when it comes to currency conversions—from pesos to
American dollars, for example—because it actually does its homework. It goes online to
download up-to-the-minute currency rates to ensure that the conversion is accurate.
(Choose Convert Update Currency Exchange Rates.)
Tip: If you Control-click (or right-click) the Calculator's results display, the shortcut
menu offers an option called Large Type. If you choose it, you get huge, enormous,
gigantic type, superimposed upon a smoky background window for contrast—a great way
to make sure the peons in the back row can see the answer.